Sensing and feedback for row on sun tracking method and system

Abstract

A solar tracker system comprising a plurality of on sun trackers and a plurality of off sun tracker. Each tracker is selectively adjusted to achieve a desired power output of the solar power plant system in an example.

The invention claimed is: 
     
       1. A solar power plant comprising:
 a solar tracker supporting a plurality of solar modules; 
 a drive device coupled to the solar tracker and configured to rotate the solar tracker about an axis; 
 a charging panel supported by the solar tracker and configured to power the drive device and to charge a battery supported by the solar tracker; and 
 a controller in communication with a memory, the memory storing thereon instructions that when executed by the controller cause the controller to:
 receive forecast data for the solar power plant; 
 determine, based on forecast data, a diffuse angle adjustment; and 
 output a signal to the drive device to rotate the solar tracker to a desired angle based on the diffuse angle adjustment. 
 
 
     
     
       2. The solar power plant of  claim 1 , wherein the diffuse angle adjustment modifies a solar tracker target angle based on a sun position angle. 
     
     
       3. The solar power plant of  claim 2 , wherein the diffuse angle adjustment is a gain factor applied to the solar tracker target angle. 
     
     
       4. The solar power plant of  claim 2 , wherein the controller further executes an instruction to determine whether the solar tracker is in a backtracking mode. 
     
     
       5. The solar power plant of  claim 4 , wherein when in a backtracking mode, the diffuse angle adjustment is a diffuse backtracking angle adjustment. 
     
     
       6. The solar power plant of  claim 1 , wherein the forecast data is received periodically. 
     
     
       7. The solar power plant of  claim 1 , wherein the memory further stores a topography of the solar power plant. 
     
     
       8. The solar power plant of  claim 7 , further comprising a solar tracker target angle, wherein the solar tracker target angle is determined based on the topography of the solar power plant. 
     
     
       9. The solar power plant of  claim 1 , further comprising a diffuse fraction index, wherein the diffuse fraction index correlates the forecast data with a diffuse angle adjustment. 
     
     
       10. The solar power plant of  claim 9 , wherein the controller applies the diffuse angle adjustment to modify a solar tracker target angle for the solar tracker. 
     
     
       11. The solar power plant of  claim 10 , wherein the solar tracker target angle is based on a sun position angle and a topography of the solar power plant. 
     
     
       12. The solar power plant of  claim 11 , wherein the sun position angle is calculated from a latitude and longitude of the solar tracker and a time of day. 
     
     
       13. The solar power plant of  claim 1 , further comprising a local solar measurement device. 
     
     
       14. The solar power plant of  claim 13 , wherein the local solar measurement device is selected from the group consisting of a solar panel, optical sensor, thermal sensor, radiation sensor and combinations thereof. 
     
     
       15. The solar power plant of  claim 13 , wherein the local solar measurement device is a photovoltaic reference cell. 
     
     
       16. The solar power plant of  claim 13 , wherein the local solar measurement device is a weather station configured to measure weather within the solar power plant and generate local weather data. 
     
     
       17. The solar power plant of  claim 13 , wherein the controller further executes an instruction to transmit local weather data to an external weather forecasting service. 
     
     
       18. The solar power plant of  claim 17 , wherein the received forecast data is from the external weather forecasting service. 
     
     
       19. The solar power plant of  claim 18 , wherein the controller further executes an instruction to query the external weather forecasting service to periodically receive the forecast data.